Telegraphic transmitter



March 25 1.924.

E. EHRHARDT TELEGRAPHIC TRANSMITTER Filed Nov. 23, 1920 allllllllll Patented li ter, 25, @2 1, d i

ERWIN EHRHfiJZtDT, F EERMFeDGR-F, NEAR BEHLIIXE, GERMANY, ASSIG-NQH T9 SIEMEN & HALSKE, AKTIEHGEEEELLSfiHAFT, 0F EKEIl-EENSSTAD'IF, NEAR EERLHT, G'EIiM/iji fi, A HEAR GORP'OMTEUN.

Tanner-entire raausrrirraa.

Application filed November 563;, 192th Serial No. cac et,

(GEJHE'TED UP-253E355 THE PRGVISKGNS 95' THE AGE 0Tb EEARCE 3, 192$, (11 STAT. L, 1313.}

To aZZ whom it may concern." successively at the operators speed in one Be it known that I, Enwm EHRHARDT, sense or the other in a suitable combination, 55 a German citizen, and residing at Hermsthis device operating in conjunction with dorf, near Berlin, Germany, have invented a power controlled device by which these 15 certain new and useful Improvements in condensers are subsequently discharged over Telegraphic Transmitters, of which the folthe line for the transmission of the signal lowingis a specification. at a uniform rate of speed controlled by The invention relates to an arrangement the driving power. Such a device is pracfor telegraphic transmitters of the kind in tioally sub ect to no wear at all so liar as to which the different signals which may be the accumulating feature is concerned and I given in succession on the keyboard at is very reliable in operation, since the ac- HOD-UnifOlUl rate of speed, are accumulated, cumulators involve no moving parts. Oi to be subsequently sent over the line in the course, the operator, for practical reasons, same succession but at a uniform rate of should not have unlimited liberty in choosifi speed. An arrangement of this kind has the ing his operating speed but he is bound by advantage that theoperator is not bound a special device within certain reasonable to keep exactly in. step with the speed of the limits, though within these limits he may 7 transmission over the line, usually effected choose his speed at will. by motor driven devices, but that neverthe- In the drawings Figure 1 diagrammatiless the line is utilized in the best manner. cally shows a constructional form of the In arrangements of this kind'as hithcrinvention by way of example. Figure Q to constructed the accumulating device is illustrates a detail. of mechanical construction. It usually 0011- The new transmitting apparatus substansists of a drum provided with pins which tially consists of three parts that is to 2 are arran ed in groups so as to correspond say a key board A, an accumulating device to the individual signals to be sent in suc- B, and a transmitter (l. The accumulating cession and which are set by the. key on the device and the transmitter are shown in keyboard according to the kind of signal Figure 1 as being turned at an an 'le of and the contacts are closed corresponding to the shafts connected therewifii for as to the setting of thepins, which contacts the purpose of representing the whole ar effect the transmission of the signals set in rangement in one diagrammatic view. For the accumulating device in'uniform succesthe sake of clearness all sliding contacts 85 sion over the line, This mechanical arfor supplying the electrical current to movrangement of the accumulating device conable parts are omitted in this figure. Such a sists of a great number of removable indiparts will be apparent from Figure 2 showvidual parts and is therefore complicated ing' an end view of the accumulating device and liable to disturbance during the operaas well as of the transmitter; For the same ac tion. reason the transmission of only three sig- Even devices, heretofore used, which take nals will be explained. The transmission an advantage of condenser charges and disof the three signals is efi'ected by operating charges as means for storing up the signals, the one or the other of two keys 1 and 2, require the operator to work in full synor both simultaneously. Accordingly, the chronism with the automatic device which accumulating device B consistsof two statransfers the storedsign'als to the line at tionary contact rings 3 and 4 over which as uniform speed, in order to utilize the line slide brushes 5, 6 and 7, 8 provided on two to the best efficiency. contact arms 9 and 10, respectively. he

These disadvantages are overcome acbrushes 5, 6 and 7, 8'are connected by cording to the present invention by making means of collecting rings 80 (Fig. 2) use of an accumulating arrangement whose with the associated parts of the system as w speed is solely dependent upon the sending will be explained afterwards. The contact speed of the operator, and which consists arm 10 is rotated by a pawl and ratchet of electric condensers arranged in groups, mechanism 12 13 actuated by an electro: we which when the key is depressed are charged magnet 11. The contact arm 9 is connected with a shaft 14 operated by a motor 19 through a gear wheel 15 and pinion '16 and a clutch 17, 18. The motor 19 simultaneously conveys movement to the contact arm 22 of the transmitterC provided with brushes 20,'2l. The brushes 20, 21 of this transmitter are connected with the system by slip rings 81 and slide on two contact rings the one of which is provided with two contact-pieces 23, 24 and the other with one contact-piece 25. The gearing 15, 16 is such that the contact arm 9 performs one sixth revolution during one complete revolution of the contact arm 22. The six contact-pieces 43, 44; 50, 51, of the rings 3, 4 of the accumulating device B are connected with the one coating of condensers 45, 47; 52, 53, i. respectively, the other coatin of which are connected with a contact 2 of the key board A and a neutrally adjusted polarized line-relay B, so that they are also in communication with the transmitter C. The armature 28 of the relay R is connected with the line L so that it may be connected with the battery 29 or 30. The keys 1 and 2 operate together with contacts 31, 32; 33, 34, respectively, which connect the key-levers with the positive or negative terminal of a split battery 35. When operating any one of the keys another contact 36 is closed in addition to the contact 27 whereby a circuit through a batter '37 and an electromagnet 11 is establishe The clutch 17, 18 between the motor 19 of the transmitter C and th accumulating device B is operated by an rmature lever 40 actuated by electromagnets 38, 39. The clutch 17, 1.8 will be thrown in and out of gear accordin whether electromagnet 39 or 38 is energized.

The operation of the transmitter is, as follows:

The key 1 being depressed the key-lever will engage the lower contact 32. Thus the key-lever will become disconnected from the positive terminal and connected with the negative terminal of the batter 35. At the same time the contacts 27 an 36 will be closed since the movable axis 41 of these contacts will be turned by means of lugs 42 at the key-levers. Assuming the brushes 5, 6 of the contact arm 10 of the accumulating device B are touching'the contact pieces 43, 44the following circuits are established: from the negative terminal of the battery 35 over contact 32, key-lever 1, brush 5, contact-piece 43, condenser 45, connection 46, contact 27 to themiddle of the split battery-35, and from the positive terminal of the battery 35 over contact 33, key-lever 2. brush 6, contact-piece 44, condenser 47. connection 46. contact 27 to the middle of the split battery 35. Therefore, the condensers 45 and 47 are supplied with current and charged with opposite polarities.

ation of the electro-magnet 11 and At the same time by the contact 36 a circuit is closed through the battery 37 and the electromagnet 11. This attracts its armature 48 and moves the pawl 12 downwards which engages the adjacent tooth of the ratchet wheel 13. When the key 1 is released the contacts operated thereby are opened and the circuit through the electromagnet- 11 is broken. Therefore, the armature 48 and the pawl 12 will be moved u wards by a spring 49th'ereby rotating t e contact arm 10 in the direction of the arrow until the brushes 5, 6 get into connection with the contact-pieces 50, 51 of the rings 3, 4. The condensers 45, 47 now remain in the charged condition which they attained by the operation just described.

If now for transmitting the following signal both keys 1 and 2 aredepressed the following circuits are established: from the negative terminal of the battery 35 to contact 32, key-lever 1, brush 5, contact-piece 50, condenser 52, connection 46, contact 27 to the middle of the battery 35, and from the negative terminal of the battery 35 to contact 34, key-lever 2, brush 6, contactpiece 51, condenser 53, connection 46, contact 27 to the middle of thebattery 35. Therefore, the two condensers 52, 53 are charged with the same polarity. The operi aw 12 as well as the rotary movement 0 the contact arm 10 takes place in the manner above described.

Thus, the condensers connected with the contact-pieces of the contact rings 3 and 4 may be charged with diiferent larities and, accordingly, the signals pro need by the keys in the key-board accumulated. The transmission of the signals over the line L is effected, as follows:

Assuming, the condensers 54, 55 have been charged over the brushes 5, 6 of the contact arm 10 with different polarities, as for instance, the condenser 54 with a positive and the condenser 55 with a negative charge. If now the brushes 7, 8 of the contact arm 9 get into connection with the contact pieces 56, 57, the crush 21 of the transmitter arm 22 touches the contact piece 23 of the transmitting device C. Therefore, the. following circuit is established: contact-piece 23, brush 21, line relay R, connection 46, condenser 54, contact-piece 56, brush 7, connection 60, contact-piece 23. The condenser 54 becomes discharged and the. line-relay R actuates its armature 28 in accordance with this operation of the condenser 54. Accordingly, an impulse from the battery 29 will be sent into the line L. "When the brush 21 gets in connection with the contact-piece 24 the circuit of the condenser 54 is broken and the discharging circuit ofthe condenser 55 closed over brush 8, connection 61, contact-piece aceacoa 24., brush 21, relay R and connection ac. The line relay R will, therefore, actuate its armature 28 so as to connect the line L with the battery 30.

The inner contact-ring of the transmitter C will only come into operation if the brush 20 is passing its contact 25 and the brush 21 has become inoperative It serves switching purposes in case the two contact arms 9 and 10 interfere with each other in their opera tion. If, for instance, the operator in attending to his service at the key board gives a number of signals more quickly than the line transmitter will be able to transmit a contact spring 66 of the arm 10 gets into connection with a contact-piece 67 provided at the hub 68 of the contact arm 9. In this case a circuit is established from battery 37, contact spring 66, contact-piece 67, connection 78, electromagnet 69, incandescent lamp 26 to battery 37. The lamp 26 is lighted and the electromagnet 69 attracts its armature 70 thereby moving a locking bar 71 in the path of the keys. Therefore, the keys become inoperative until by the further movement of the contact arm 9 the contact 67 gets out, of connection with the contact spring 66 so that the electro-magnet 69 becomes de-energized, the locking bar 71 released and the lamp 26 extinguished, thereby indicating to the operator that he may attend to his service again. I

If, on the other hand, the operator is too slowly in-giving signals the contact arm 9 will so quickly advance compared with contact arm 10 that a contact-piece 73 provided in the hub 68 gets into connection with the contact-spring 66. A circuit is established, thereby, from battery 37 to spring 66, contact-piece 73, connection 74, electromagnet 38, brush 20, contact-piece 25, connection 7 5 to battery 37. The electromagnet 38 is energized and attracts its armature 40 so that the clutch-portions 17, 18 become disengaged and the contact arm 9 of the accumulating 1 device B disconnected from the motive power of the line-transmitter C. The clutchportions 17, 18 become engaged again by means of another contact-piece 76 in the hub 68. At the next step of the arm 10 this contact-piece 76 comes into connection with the spring 66, whereas the contact-piece 73 is released. Therefore, a circuit is-established from battery 37 to spring 66, contactpiece 76, connection. 77, electromagnet 39, brush 20, contact-piece 25, connection 75 to battery 37. The electromagnet 39 is venergized and the clutch-portions 17, 18, are throw-n'into gear so that the contact arm 9 will take up its normal operation again. The contact-pieces 67, 73 and 76 are connected with collecting rings 82, the brushes of which are electrically connected with the associated parts of the system. The collect- 1 means for su ing ring 83 supplies current to the brush 66,

signals, a key ioarol and a signal accumulatmg device, comprising a plurality of groups of condenseis electrically associated \vithsaid keyboard according to the composition of the individual signals represented on the board, means for permitting the separate charging of said individual condenser groups successively at a nonuniform rate of speed depending on the operating speed of the keyboard, a sending device adapted to transmit signals to the line, said device operating at a uniform rate of speed, and means cc trolled by the sending device for successively discharging said condensers at a uniform rate of speed into said sending device, to cause the signal transmission to the line at a uniform speed rate.

2. In a telegraphic transmitter, a line, means for supplying current for producing signals, a keyboard and a signal accumulat in'g device, comprising a plurality of groups of condensers electrically associated with said keyboard according to the composition of the individual signals represented on the board, means for permitting the separate charging of said individual condenser groups successively at a non-uniform rate of speed depending on the o crating speed of the keyboard, a sending evice adapted to transmit signals to the line, said device operating at a uniform rate of speed, and means controlled by the sending device for successively discharging said condensers at a uniform rate of speed into said sending device, to cause the signal transmission to the line at a uniform speed rate, and means for limitin the lag and lead of the keyboard speed relatively to the line sending speed.

3. In a telegraphic transmitter, a line, means for supplying current for producing signals, a keyboard and a signal accumulating device, comprising groups of contact segments, a group of condensers connected to each segment group, a group of brushes equal in unit size to the size of said segment groups and cooperating with the segments thereof, and suitably operated by and electrically connected with said keyboard to succesively pass over said segment groups at the speed rate at which the signals are given on the board, to cause the charging of said condensers from said current supply means in accordance with the character of the signal desired, a sendingdevice operating at a uniform rate of speed and said condensers for transmissmn to the line at a uniform speed rate, and a second group of brushes similar in size to the first group and cooperating with said segment groups adapted to suc-' cessively receive the discharge currents of and mechanically operated by and in a fixed time relation to said sending device, said brushes adapted to connect said condenser groups for discharge successively with said sending device.

4, In a telegraphic transmitter, 'a line,

means for supplying current for producing,

signals, a key oard and a signal accumulating device, comprising groups of contact segments, a group of condensers connected to each segment group, a group of brushes equal in unit size to the size of said segment groups and cooperating with the segments thereof, and sultably operated by and electrically connected with said keyboard to successively pass over said segment groups at the speed rate at which the signals are given on the board, to cause the charging of said condensers from said current supply condenser groups for discharge successively with said sending device, means for'breaking the mechanical connection between said sending device and said second group of brushes when the keyboard speed lags behind the sender speed beyond predeterminedlimits, and means for blocking the operation of said keyboard when the keyboard speed leads the sender speed beyond predetermined limits.

5. In a telegraphic transmitter, a line, means for supplying current for producing signals, a keyboard and a signal accumulating device, comprising groups of contact segments, a group of condensers connected to each segment group, a group of brushes equal in unit size to the size of said segment groups and cooperating with the segments thereof and suitably operated b and electrically connected with said hey oard to successively pass over said se ent groups at the speed rate at which the slgnals are given on the board, to cause the charging of said condensers from said current supply means in accordance with the character of the signal desired, a sending device comprising a. line relay adapted to send current impulses of varying polarity into said line, and a distributor'controlling the energizing of said relay and adapted to operate at a uniform rate of speed, a second group of brushes similar in size to the first group and gliding over said segment groups and mechanically operated by and in fixed time relation to said distributor, brushes adapted to connect said condenser said groups for dischar e successively to said distributor to energize. said line relay at a uniform rate of s eed and in accordance with the polarity o the condenser discharge currents.

In testimony whereof I afiix my signature.

ERWIN EHRHARD T. 

